________is dangerous for us to swim in the river alone.
A. It B. That C. This
Mary called and asked her husband home at once, because she locked her daughter in the home.
| A．to leave | B．leave | C．go | D．to go |
When you at a restaurant, please order just enough food.
| A．ate | B．will eat | C．eat | D．have eaten |
It’s very important for us to learn how to learn by .
| A．ourselves | B．itself | C．myself | D．themselves |
---Excuse me, could I take this seat?
---Sorry, __________.
| A．here you are | B．take it | C．it’s taken | D．never mind |
---I’ll go to the USA next month.
---__________ for?
| A．Why | B．How | C．Which | D．What |