Acceptable sentences

[basic learner]

Dear teachers,

I have the following sentences which I am not sure of their correctness. Some help is needed .

1. Is it correct to say : " What is your weight ? or " How much
do you weigh ?

2. " I have attained success in all my exams " or " I have
attained success in all of my exams."

3. Is it correct to say : " I go first ( to leave a place ) or " I
take a leave now"

Thanks for help.

[MikeNewYork]

Dear teachers,

I have the following sentences which I am not sure of their correctness. Some help is needed .

1. Is it correct to say : " What is your weight ? or " How much
do you weigh ?

2. " I have attained success in all my exams " or " I have
attained success in all of my exams."

3. Is it correct to say : " I go first ( to leave a place ) or " I
take a leave now"

Thanks for help.

1. Both are correct.

2. Both are grammatical but unnatural. I suggest "I have passed all my exams or all of my exams."

3. Both should be future tense. "I'll go first" (but that usually refers to taking the first turn (as in a game) instead of leaving) and "I'll take my leave now." (very formal)