चाय मीठी है।

Because चाय is a feminine noun in Hindi, and the adjective मीठा changes to match it.

• masculine singular: मीठा
• feminine singular: मीठी

So:

• मीठा आम = a sweet mango
• मीठी चाय = sweet tea

In चाय मीठी है, the adjective agrees with चाय, so मीठी is correct.

Yes, in standard Hindi, चाय is treated as a feminine noun. That is why words connected to it usually take feminine forms.

For example:

• गरम चाय = hot tea
  (गरम does not change here)
• अच्छी चाय = good tea
• मीठी चाय = sweet tea

So even though grammatical gender may feel arbitrary to an English speaker, you simply need to learn चाय as feminine.

है is the present-tense form of to be for he/she/it/this/that and for singular nouns.

So the structure is:

• चाय = tea
• मीठी = sweet
• है = is

Together: Tea is sweet or The tea is sweet, depending on context.

In Hindi, sentences like this usually keep the verb to be, so है is an important part of the sentence.

Hindi commonly uses subject + complement + verb order.

So:

• चाय = subject
• मीठी = description/complement
• है = verb

That gives:

चाय मीठी है = Tea sweet is

This is normal Hindi word order. English puts is before the adjective, but Hindi usually puts the verb at the end.

Yes. Hindi does not have articles like a, an, and the.

So चाय मीठी है can mean:

• Tea is sweet
• The tea is sweet

The exact meaning depends on context.

If you are talking about tea in general, it may mean tea is sweet.
If you are talking about a specific cup of tea, it may mean the tea is sweet.

Yes, but it usually feels different.

• चाय मीठी है = The tea is sweet
  This is a full statement about the tea.
• मीठी चाय है = literally There is sweet tea or It is sweet tea, depending on context

So if you want to describe the tea directly, चाय मीठी है is the most straightforward sentence.

Also note the difference between:

• मीठी चाय = sweet tea
• चाय मीठी है = the tea is sweet

The first is a noun phrase; the second is a complete sentence.

A simple pronunciation guide is:

chāy mīṭhī hai

Roughly:

• चाय = like chai
• मी = mee
• ठी = thee, but with a retroflex ṭh sound made with the tongue curled back
• है = often sounds like hai or sometimes a bit like heh in natural speech

A more careful breakdown:

• चाय → chaay
• मीठी → mee-thee with a retroflex ṭh
• है → hai

It can come before the noun, but that changes the structure.

• मीठी चाय = sweet tea
  This is just a noun phrase.
• चाय मीठी है = the tea is sweet
  This is a full sentence.

So:

• before the noun = adjective directly modifying the noun
• after the noun + है = saying something about the noun

English uses sweet tea and the tea is sweet too, so the difference is actually similar.

Yes. For plural subjects, Hindi usually uses हैं instead of है.

For example:

• चाय मीठी है = the tea is sweet
• चायें मीठी हैं = the teas are sweet

Also, with plural feminine nouns, the adjective may stay in a feminine plural form depending on the adjective type and the sentence structure. In this case, मीठी works with feminine plural as well, while the verb changes clearly to हैं.

Yes, मीठा is a changeable adjective. Many Hindi adjectives ending in -ा change like this:

• masculine singular: मीठा
• feminine singular: मीठी
• masculine plural: मीठे
• feminine plural: मीठी

Examples:

• मीठा फल = sweet fruit
• मीठी चाय = sweet tea
• मीठे आम = sweet mangoes

This is an important pattern in Hindi, so मीठी in this sentence is a very useful example of adjective agreement.