that is or that are

[allthewayanime]

I would like to know if after 'that' we use a singular or a plural verb.For instance:

e.g. That's the cups I bought yesterday.
That are the cups I bought yesterday.

[Raymott]

I would like to know if after 'that' we use a singular or a plural verb.For instance:

e.g. That's the cups I bought yesterday. No. (I'm simplifying. This is possible in very informal speech, just as "There's the cups I bought" is possible. But I'd suggest you become familiar with the traditional forms before trying to become too colloquial.)
That are the cups I bought yesterday.
No, you can't say "That are ..." No exceptions here.

The plural of 'that' is 'those', just as the plural of 'this' is 'these'.
"That is the cup I bought yesterday"; "Those are the cups I bought yesterday"
"This is the cup I bought yesterday"; "These are the cups I bought yesterday"

[5jj]

Those are the cups I bought yesterday.

[allthewayanime]

Could someone explain me why in this passage(taken from a book) the verb is used in the singular form after 'that'?

'Drink some tea.'
'I don't f**king want any fucking tea.'
'That's two f**kings in the space of 3 seconds.I think you need some tea.
'I'm really sorry.'

[5jj]

I don't think we can take the people in that dialogue as examples of speakers of the best English. In any case, as Raymott has already said, that's is possible in very informal speech.

[bhaisahab]

Could someone explain me why in this passage(taken from a book) the verb is used in the singular form after 'that'?

'Drink some tea.'
'I don't f**king want any f**king tea.'
'That's two f**kings in the space of 3 seconds.I think you need some tea.
'I'm really sorry.'

Please don't use potentially offensive words. This is a different case entirely, as in, "that is two sixes in a row for Tendulkar", for example.

[5jj]

This is a different case entirely, as in, "that is two sixes in a row for Tendulkar", for example.

. bhai's answer is more accurate/relevant than mine.

[allthewayanime]

Thank you very much for replying and I excuse myself for the potentially offensive words.