tab

keep tabs (或 a tab) on

(informal)monitor the activities or development of; keep under observation

(非正式)监控…的活动（或进展）；密切注意

pick up the tab

(informal, chiefly N.Amer.)pay for something

(非正式，主北美)付账；承担费用

my company will pick up the tab for all moving expenses.

我公司将承担搬迁的所有费用。

keep tabs on【非正式用语】

To observe carefully

密切注意

Let's keep tabs on expenditures.

让们密切注意开支情况