30. There are people can’t help ( laugh )when they see someone ( slip ) on a banana skin 31. He went to bed without ( lock ) the doors .

32. They don’t have enough patience ( wait ) for him .

33. Gravity makes water ( run ) downhill .

34. This man let me ( use ) his phone yesterday.

35. Are we allowed ( go ) out with Tom ?

36. The teller was made ( raise ) his hands .

37. Mary was advised ( stay ) out of the crowd .

38. She prefers ( eat ) to ( prepare ) meals .

39. When the rainy season comes , you need ( repair ) the roof of the house .

40. The flowers need ( water ) but you needn’t ( water ) them now.

Hãy viết PTHH biểu diễn phản ứng hóa hợp của lưu huỳnh với các kim loại sau. (Biết trong hợp chất S có hóa trị II).

a) Nhôm     

b) Sắt          

c) Chì          

d) Natri.