Sometimes words alone were not enough to _________pupils along the path of knowledge
An idea came to him ___ he might do the experiment in another way.
It is so wet there that the trees are extremely tall, some ________ over 90 metres.
Rather than ___ on a crowded bus, Tom always prefers __ a bicycle.
Perseverance is a kind of quality --- and that’s ________ it takes to do anything well.
A heavy learning burden leads to unhealthy behaviors such as poor eating habits, which ___ damage the health of students.