Question

1. When you telephone from abroad, you should dial 096 first.

2. When you are telephone from abroad, you should dial 096 first.

3. Telephoning from abroad, you should dial 096 first.

4. Telephoned from abroad, you should dial 096 first.
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Which ones are grammatical?

Answer 1

Sentence 1 is the best; sentence 3 is next best.

Sentences 2 and 4 are incorrect.