conditional
have conditions in doing sth
be able to
be capable of
例句：
1 But any cease-fire must have conditions in it so that Hamas does not use Gaza as a place from which to launch rockets," he said."
但是任何停火必须有条件,让哈马斯不能利用加沙为发射火箭弹的基地.
2 It was disappointing not to be able to see her.
不能见到她真令人失望.