Cut back

剪短；修剪(枝叶等)

He cut back some shoots on this tree.

他剪掉了这棵树上的一些嫩枝。

削减，减少，缩减

They had to cut back on their family expenses.

他们不得不削减家里的开支。

Cut down

砍倒

He cut down the tree behind the house.

他把房子后面的那颗树砍倒了。

削减；缩减

Because of the poor management of the company, they had to cut down some staff.

由于公司管理不善，他们不得不裁掉一些员工。