1. His family is large.

Question

2. His family are all healthy.
3. His family members are all healthy.
4. The members of his family are all healthy.
5. There are 50 families in this apartment building.
6. There are 50 families in these apartment buildings.
7. There live 50 families in this apartment building.
8. There live 50 families in these apartment buildings.
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Are they all grammatical? Does #3 and #4 mean #2? Do you use Sentence 2 in the USA?In British English #2 is okay, isn't it?

Answer 1

I would use these:
1, 3, 4, 5, and 6.

7 and 8 are incorrect unless you rephrase and say, "Fifty families live in .... " (Remember, don't start a new sentence with a numeral; the number word needs to be spelled out.)

Answer 2

Thank you.

2. His family are all healthy.
2-1. His family is all healthy.

[Which one do you use?]

Answer 3

Family is singular. It's one family unit. Use the singular verb form is. Are is for a plural subject as in family members (more than one member).

Answer 4

1.   Which of the following passages from the novel best illustrates the most extreme hostility  between the Chinese and American communities in San Francisco?