Question

.Who had sent the couriers and where?Who were the couriers looking for?​

Answer 1

It would also be correct to state: “The courier has already left”, or “We have sent the courier”.

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1. The first one is in the present perfect tense.
2. For example, you have sent him two letters. ( ...
3. Before they talked to you over the phone, you had sent them two letters

Answer 2

A courier service is a premium, all-inclusive service which collects and delivers shipments in the shortest possible time frame, while postal services are generally used for transporting letters and parcels which can sometimes take some time to arrive at their final destination.

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