You are under 18 years old, so it is for you to join the Trailwalker.

Timmy goes to school _____ every day. It’s 5 minutes’ walk from his home to school. [ ]

We __________ 1000 English words since we __________ to learn English.

Is this museum ___________ he wishes to visit?

The fact has worried the people across the world ___________ the earth is becoming warmer and warmer these years.