यह गोली दिन में एक बार लेनी है।

No. गोली can mean different things depending on context.

Here it means pill/tablet/medicine pill, not bullet.

Common meanings:

• गोली = pill, tablet
• गोली = bullet
• sometimes even a small round object, depending on context

In a medical sentence like यह गोली दिन में एक बार लेनी है, the meaning is clearly pill/tablet.

यह literally means this.

In this sentence, it points to the pill being talked about:

• यह गोली = this pill

In natural English, you might translate the whole sentence without always saying this, but in Hindi the sentence is directly referring to the pill in front of the speaker/listener or the one being discussed.

Also note:

• यह = this
• वह = that

In speech, यह is often pronounced more like ये in everyday conversation, but the written form here is standard.

दिन में literally means in a day or within the day.

Breakdown:

• दिन = day
• में = in

So:

• दिन में एक बार = once in a day / once a day

In this kind of instruction, दिन में expresses frequency, not just time of day. It does not necessarily mean during the daytime only. It means per day.

Because बार means time/occurrence in the sense of number of times.

So:

• एक बार = one time = once
• दो बार = two times = twice
• तीन बार = three times

In frequency expressions:

• दिन में एक बार = once a day
• दिन में दो बार = twice a day

This is a very common pattern in Hindi.

Because लेनी agrees with गोली, which is a feminine noun.

The verb here comes from लेना = to take. In this structure, the infinitive-like form changes to agree with the thing being taken:

• masculine singular: लेना
• feminine singular: लेनी
• masculine plural: लेने
• feminine plural: usually लेनी with plural context depending on construction, though other parts of the sentence may show the plural more clearly

Since गोली is feminine singular, Hindi uses:

• गोली ... लेनी है

Compare:

• यह फल खाना है। = This fruit is to be eaten.
• यह दवा लेनी है। = This medicine is to be taken.

So the form matches the grammatical gender of the object being talked about.

लेनी है expresses obligation, instruction, or what is supposed to be done.

A useful way to understand it is:

• लेनी है = has to be taken / is to be taken

So the sentence has the sense of a medical instruction:

• This pill is to be taken once a day
• or naturally, Take this pill once a day

This structure is very common in Hindi:

• मुझे जाना है। = I have to go.
• यह किताब पढ़नी है। = This book has to be read.
• दवा लेनी है। = The medicine has to be taken.

So it is not just a plain future tense. It carries a sense of requirement or instruction.

Because Hindi often leaves out subjects when they are obvious from context.

In a medical instruction, the implied meaning is something like:

• आपको यह गोली दिन में एक बार लेनी है। = You have to take this pill once a day.

But Hindi often omits आपको if the instruction is already clearly directed at the listener.

This omission is very common and natural.

So:

• यह गोली दिन में एक बार लेनी है। still clearly means that the listener/patient should take it.

Yes, both can be used, depending on context and style.

Common verbs with medicine:

• लेना = to take
• खाना = to eat, but also commonly used for pills/medicine in everyday Hindi

Examples:

• दवा लेनी है। = The medicine has to be taken.
• दवा खानी है। = The medicine has to be taken.
• गोली लेनी है। = The pill has to be taken.
• गोली खानी है। = The pill has to be taken.

Nuance:

• लेना sounds a bit more general and often slightly more formal or neutral for medicine instructions.
• खाना is very common in everyday speech for tablets or oral medicine.

You may also hear:

• पीनी है for liquids
  • यह दवा दिन में दो बार पीनी है। = This medicine is to be drunk twice a day.

है is the present tense form of to be for singular subjects in many contexts.

In this sentence, it completes the obligation/instruction structure:

• लेनी है = has to be taken / is to be taken

Without है, the sentence would sound incomplete in standard Hindi.

Compare:

• मुझे जाना है। = I have to go.
• तुम्हें पढ़ना है। = You have to study.
• यह गोली लेनी है। = This pill has to be taken.

So है helps express the present instruction or requirement.

The given word order is very natural:

• यह गोली दिन में एक बार लेनी है।

Hindi word order is somewhat flexible, but not completely free. You could rearrange parts for emphasis, for example:

• यह गोली एक बार दिन में लेनी है।
• दिन में एक बार यह गोली लेनी है।

These are understandable, but the original sentence sounds the most standard and natural for a neutral instruction.

A helpful way to view the original order:

• यह गोली = topic/item
• दिन में एक बार = frequency
• लेनी है = required action

No, not in this expression.

The correct phrase is:

• दिन में एक बार = once a day

Here बार is part of a frequency expression, and it does not take को.

You may see को in other time expressions, such as:

• सोमवार को = on Monday
• एक बजे को is not standard, but एक बजे = at one o’clock

So for once a day, the natural Hindi pattern is simply:

• दिन में एक बार

You only need to change the number before बार:

• दिन में एक बार = once a day
• दिन में दो बार = twice a day
• दिन में तीन बार = three times a day

So:

• यह गोली दिन में दो बार लेनी है। = This pill is to be taken twice a day.
• यह गोली दिन में तीन बार लेनी है। = This pill is to be taken three times a day.

This is a very productive and useful pattern for medicine instructions.