Concept:
Tendering is a procurement method used for purchasing medicines and supplies.
Step 1: Long-term tendering.
In long-term tendering, supply arrangements are made for a longer period.
Step 2: Cost benefit.
Bulk and planned purchasing can reduce purchase cost.
Step 3: Supply benefit.
It also ensures regular and continuous availability of medicines.
Step 4: Final answer.
Thus, long-term tendering is preferred to reduce cost and ensure continuous supply.
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\boxed{\text{Reduce cost and ensure continuous supply}}
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