Let’s go to the museum. Many ancient things are __________ in it.
—We’ll make a trip to Hainan Island next weekend. Will you go with us?—No, I can’t _____ it at present because I have little money.
Science is _____ difficult for some students ____ learn, so many of them don’t like it.
【原创】There are so many kinds of pens in the shop ,I can’t decide __.
—I will go to Dalian with my parents next month. —________
He hardly worries about his English, _______ ?