【題目】If you live in Beijing or Shanghai, you can try out the Mobike app just to see how many bikes ______ around you.

【題目】Most colleges will allow students ______ their major choices.

【題目】Only 3 per cent of the world’s water is fresh water. The rest ______ salt water.

【題目】I need to amuse myself so I won’t keep ______ about things.

【題目】The weather expert predicted that the coming typhoon ______ destructive.

【題目】I’m not sure yet ______ I think I will study medicine in the future.

【題目】Housing is very expensive in this city. The prices ______ up again since last month.

【題目】The more carefully you dive, the ______ you will be.

【題目】Old people may feel ______ if they live alone for a long time.

【題目】Sightseeing in the town is best done ______ by tour bus or by bike.