2 no more than adv. 只是;僅僅
Each class has no more than 8 students.
每個班級的學生不超過8個。
not more than不超過;至多;不比…更…
And the earholes are not more than three.
還有耳洞不能超過三個。
3 what是做的主語, 但好像是狀語從句的主語
4 我覺得兩個都可以