1.        I known about the delay, I would have left earlier. (Had / If / Were)

2. You can stay,        you follow the rules. (provided that / unless / had)

3.        she to apply, she would certainly succeed. (Were / Had / Should)

4. If I        so busy last year, I would be more experienced now. (hadn't been / wasn't / weren't)

1. Take an umbrella        it rains. (in case / unless / if)

2. I will help you,        you ask politely. (as long as / in case / unless)

3.        you need any assistance, please call us. (Should / Would / Had)

4. We wouldn't have arrived late        the traffic. (but for / despite / if)

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