a pair of shears的用法和样例：
- He is cutting the branches with a pair of shears.
- There goes but a pair of shears between them.
- I bought a pair of tan leather shoes the other day.
- Billy has a pair of new trousers.
- Marriage resembles a pair of shears,so joined that they cannot be separated; often moving in opposite directions,yet always punishing anyone who comes between them.