He 20 dollars for his old bike the other day.
| A．paid | B．took | C．spent | D．offered |
Last night, there were millions of people ______ the opening ceremony live on TV.
| A．watch |
| B．to watch |
| C．watched |
| D．watching |
______ carefully if any change occurs when doing experiments in the lab.
| A．Observe |
| B．To observe |
| C．Observed |
| D．Observing |
Jane is in a hurry because the train to the airport leaves ______ half an hour.
| A．by |
| B．in |
| C．for |
| D．until |
--- Hi, let's go skating.
--- Sorry, I'm busy right now. I ______ in an application form for a new job.
| A．fill |
| B．have filled |
| C．am filling |
| D．will fill |
Some animals carry seeds from one place to another, ______ plants can spread to new places.
| A．so |
| B．or |
| C．for |
| D．but |