Learn Hardcore Chinese: tā xiànzài dǒng le, wǒ yě dǒng le. - Now she understands, and I understand too.

No. 了 after 懂 marks a change of state or new situation: “has come to understand / understands now.” It’s not simply past tense. With a stative verb like 懂, 懂了 means the state has newly begun.

Examples:

她懂了 = She now gets it (she didn’t before).
Without 了: 她懂 = She understands (a general fact, not highlighting a change).

Why is 了 used in both clauses? Can I drop one of them?

Each clause has its own predicate, so each uses 了 to mark the new state. If you drop the second 了:

她现在懂了，我也懂。 The second clause becomes a general statement (“I also understand (in general)”), losing the “now I get it” feel.
If you drop both: 她现在懂，我也懂。 You’re simply stating facts, not emphasizing a recent realization.

Using 了 in both keeps the parallel “now-understands” meaning for both subjects.

Where should 现在 go? Can I say 现在她懂了?

Time words usually go after the subject and before the verb: 她现在懂了. Putting it at the very beginning is also fine for emphasis: 现在她懂了. Both are natural. Don’t put 现在 after the verb in this sentence.

How does 也 work here? Where does it go in the sentence?

也 means “also/too.” It goes after the subject and before the verb/adjective:

Correct: 我也懂了。
Incorrect: 也我懂了 or 我懂也了.

In the full sentence, 我也懂了 means “I also (now) understand,” linking back to the first clause.

Could I use 都 instead of 也?

Use 也 to say “also (in addition).” Use 都 when referring to a plural subject meaning “both/all.”

Current pattern: 她现在懂了，我也懂了。
With a shared plural subject: 她和我都懂了。 / 我们都懂了。

You can combine them when the scope differs:

我们现在也都懂了。 = Now, we also (in addition to others/other things) all understand.

Can I use 还 instead of 也 here?

Not in this meaning. 还 most often means “still/yet/also (in addition)” but with a sense of continuation or “in addition to what’s already mentioned.” 我还懂了 is usually odd here. Typical uses:

我还不懂。 I still don’t understand.
我还没懂。 I haven’t understood yet.

For “also,” stick with 也.

What’s the difference among 懂, 明白, 知道, 理解, 了解, and 会?

懂: understand (often of meaning/explanation); can be immediate “got it.”
明白: understand/be clear about; close to 懂, slightly more colloquial/explicit clarity.
知道: know (facts/information), not necessarily “understand the reasoning.”
理解: understand deeply/with reasoning or empathy; more formal/deeper.
了解: have a grasp/insight into, be familiar with.
会: can/know how to (ability), not “understand.”

In this sentence, 懂了 is “now she/I get it.” You could also say 明白了 with a similar feel; 理解了 sounds deeper.

Does 懂 need an object? What’s implied here?

懂 can be transitive or intransitive.

With object: 我懂中文。, 我懂你的意思。, 我听懂了这句话。
Without object: 我懂了。 (object is understood from context) In the given sentence, “what” they understand is implied by prior context.

How do I negate forms like this? 不懂, 没懂, 还不懂, 还没懂, 不懂了—what’s the difference?

不懂: don’t understand (general/at present).
没(有)懂: didn’t understand (completion not achieved at a past point or in an attempt); more natural with a verb like 听/看: 没听懂.
还不懂: still don’t understand (contrary to expectation).
还没(有)懂: have not understood yet (but expected to).
不懂了: no longer understand (a change to not understanding).

To ask about the change-of-state: 你懂了没有？/ 懂了没？

Pronunciation tips: any tone sandhi here?

她 tā (1), 现在 xiànzài (4-4), 懂 dǒng (3), 了 le (neutral), 我 wǒ (3), 也 yě (3).
Third-tone sandhi in 我也懂 (3-3-3): the 也 before a 3rd tone becomes 2nd tone. Result: wǒ yé dǒng le.
了 here is pronounced neutral as le. The other reading liǎo occurs in different structures (e.g., 不了/得了) and not here.

Could I just say 懂了 as a response?

Yes. 懂了。 (“Got it.”) is a very common standalone acknowledgment in conversation.

Is the comma the right way to connect these two clauses? Could I use 和 or 而且?

A comma is perfectly natural. 和 connects nouns, not clauses, so don’t use it here. 而且 can connect clauses but adds “moreover,” which is heavier than needed since 也 already covers “also.” The original is the most natural.

Can I use 已经 instead of 现在? What about both?

已经 emphasizes “already”: 她已经懂了。
现在 emphasizes time “now”: 她现在懂了。
Both together are common for emphasis/context: 她现在已经懂了。 (now, already understands). Depending on context, this can be a bit redundant but is acceptable.

What’s the difference if I drop 了 entirely: 她现在懂，我也懂?

Without 了, you’re stating present facts: “She understands now; I understand too,” without highlighting a new development. With 了, you mark a new situation/realization (“now she gets it, and I do too”).

Are there verbs that combine with 懂 to be more specific, like “understand by listening/reading”?

Yes, very common:

听懂 (understand by hearing): 我听懂了。
看懂 (by reading/seeing): 我看懂了。
读懂 (by reading): 我读懂了。
弄懂 / 搞懂 (figure out, manage to understand after effort): 我终于弄懂了。

If I want to say “We both understand now,” should I still use 也?

Use 都 with a plural subject:

我们都懂了。 (We all/both understand now.) If you want to add “also” relative to something else, you can say:
现在我们也都懂了。 (Now, we also all understand.)

Can I say 我也现在懂了?

No. Place time expressions before the verb but after the subject, and keep 也 before the verb. Natural options:

我现在也懂了。
现在我也懂了。

Any note about 她 vs 他 in speech?

In speech, 她 (she) and 他 (he) are both pronounced tā. The gender distinction only exists in writing, not in pronunciation. Context clarifies in spoken Mandarin.