IV. Fill each gap of the following sentences with a suitable preposition. (5 x 0.2 = 1.0 pt)
46. How many seasons are there in a year……on…… your country?
47. When you go to the market, please buy some books and pens ……to…… me.
48. There are some trees ……in…… my house and the lake.
49. Mrs. Nhung and her friends are listening……to…… music at the moment.
50. What ……are you……… going going to Ha Long Bay with them this weekend?