他可以一起来，只要他表现良好。

He's welcome to come along, ___provided ___that he behaves himself.

最后，只要你有钱可花，你总能在购物大厅里闲逛得很开心。

Finally, ___provided ___that you have some money to spend, you can always have a great time strolling through shopping halls.

你可以使用图书馆，只要你遵守规则。

You can use the library, ___provided you follow the rules.