Learn Hardcore Chinese: zhōumò wǒmen dǎsuàn yāoqǐng péngyou lái jiā kàn diànyǐng. - On the weekend we plan to invite friends to come to our home to watch a movie.

So 周末 at the beginning simply functions as a time expression: “(At) the weekend, …”.
You can also move it: 我们周末打算邀请… — both orders are fine.
If you want to say “this weekend” more clearly, you can say 这个周末 at the front: 这个周末我们打算…

What’s the nuance of 打算? How is it different from using 要 or 会 for the future?

打算 means “plan / intend to” — it emphasizes a deliberate plan that you have thought about, not just a prediction.

Compare:

周末我们打算邀请朋友来家看电影。
→ We plan to invite friends; it’s our intention.
周末我们要邀请朋友来家看电影。
→ Also “we’re going to…”, often a bit stronger / more definite.
周末我们会邀请朋友来家看电影。
→ More like “we will invite…”, often sounds like predicting a future action or stating a likely outcome.

So 打算 highlights personal intention / plan rather than inevitability or prediction.

Can 打算 be followed directly by a noun, or does it need a verb phrase after it?

打算 is normally followed by a verb phrase (an action):

打算邀请朋友
打算去旅行
打算买一辆车

If you give it a noun, you usually turn that noun into a verb phrase, e.g. not just 打算旅行 (OK: verb) but not 打算一个旅行 (odd: noun phrase).
So in this sentence, 打算邀请朋友来家看电影 is one long verb phrase describing the plan.

Why is it 邀请朋友来家看电影 and not something like 邀请朋友到我们家看电影? What’s the difference between 来 and 到 here?

Both are possible; they just frame the action slightly differently.

来家看电影: literally “come home to watch a movie”.
来 emphasizes the direction toward the speaker (to where we are).
到我们家看电影: literally “(go) to our home to watch a movie”.
到 emphasizes arriving at a place, and 我们家 makes the destination explicit.

In casual speech, 来家 is often shorthand for 来我们家.
邀请朋友来家看电影 and 邀请朋友到我们家看电影 are both natural; the second is a bit more explicit/formal.

Why is there no 在 before 家? Shouldn’t it be 在家看电影 for “watch movies at home”?

If you say 在家看电影, you’re describing where you do the watching: “(be) at home and watch a movie.”

In this sentence, though, 来家 is focusing on motion toward home: “come (to our) home.”
So the structure is:

邀请朋友 – invite friends
来家 – to come home
看电影 – to watch a movie

If you really want both “come” and “be at home watching,” you could say:
邀请朋友来我们家在家看电影 — but that’s redundant and unnatural.
So we just say 来(我们)家看电影 and leave out 在.

Is it okay to say just 家 here? Should it be 我们家 (“our home”) instead?

Both are possible, but the nuance is slightly different.

来家看电影: in everyday conversation, this is understood as “come to (our) home to watch a movie”, with 我们 understood from context.
来我们家看电影: explicitly “come to our house” — clearer if there might be ambiguity.

In many contexts where the speaker is clearly talking about their place, 家 alone is natural and not confusing.
If you want to be very clear in a textbook-style sentence, 来我们家看电影 is a bit safer.

Why is there no plural marker 们 on 朋友? How do I know it’s “friends” and not “friend”?

In Chinese, plurality is often not marked on nouns; it’s inferred from context.

朋友 can mean friend or friends.
朋友们 exists but is used mainly:
- in addressing a group (同学们、朋友们, “friends, classmates”), or
- for emphasis / style, not as the default plural.

Here, 邀请朋友来家 naturally implies “invite (some) friends”, because you usually invite more than one person for a movie, and nothing limits it to one.
If you really want to highlight “friends” as a group, you could say 邀请朋友们, but it’s not necessary.

Why isn’t there a measure word, like 几个朋友 or 一些朋友? Don’t Chinese nouns normally need measure words?

Measure words are required when a noun is directly counted or quantified.

With a number / quantifier:
三个朋友, 一些朋友, 很多个朋友
Without a specific quantity, just the bare noun is fine:
邀请朋友, 见朋友, 和朋友聊天

In 邀请朋友, we’re not specifying how many friends, so 朋友 stands alone.
If you want to say “a few friends,” you can say 邀请几个朋友来家看电影.

Could we say 请朋友来家看电影 instead of 邀请朋友来家看电影? What’s the difference between 请 and 邀请?

Both can mean “to invite,” but their usage differs:

邀请: more formal / explicit; often used for events, parties, written invitations.
邀请朋友来家看电影 feels like “invite friends over (for an occasion).”
请: very common in everyday speech; also means “treat (someone)” to food/drink.
请朋友来家看电影 is also natural, a bit more casual.
(Note: 请朋友吃饭 = “treat friends to a meal.”)

In this sentence, both are acceptable; 邀请 just sounds slightly more “textbook” or formal.

Why is it 看电影 and not something like 看一个电影? When would you add 个 or another measure word here?

With activity verbs like 看电影, 看电视, 看书, Chinese often uses the bare noun to describe the general activity:

看电影 – watch movies / watch a movie
看书 – read (books)
看电视 – watch TV

If you emphasize one whole, specific movie, you might add a measure word:

看一部电影 / 看一场电影 – watch a movie (a whole showing / film)

In everyday planning phrases like 来家看电影, the bare 看电影 is the most natural choice; it doesn’t need 个.

Why isn’t there any 了 in this sentence? How do we express that this is a future plan and not something happening now?

Future time is signaled mainly by context and time words, not by 了.

Here, 周末 clearly sets the time as in the future.
了 often marks a completed action or a change of state, not future.
So:

周末我们打算邀请朋友来家看电影。
→ “This weekend we plan to invite friends…”
If you report it afterwards, you might say:
周末我们邀请了朋友来家看电影。
→ “This weekend we invited friends over to watch a movie.”

No 了 is needed in the original sentence because nothing has happened yet.

Can we drop 我们 and just say 周末打算邀请朋友来家看电影? Would that still be correct?

Yes, that’s grammatically fine and often happens in casual speech.

Without 我们, the subject is understood from context, usually the speaker or the speaker’s group.
So:

周末我们打算邀请朋友来家看电影。 – “We plan to…”
周末打算邀请朋友来家看电影。 – “(We) plan to invite friends…”

If the subject is obvious in the conversation, dropping 我们 feels natural and fluent.