1. it started raining when he was walking to work. He stopped a taxi because he didn't wear (wasn't wearing) a jacket and he didn't have an umbrella. ==> 1. It started raining while he was walking to work. He stopped a taxi because he wasn't wearing a jacket and he didn't have an umbrella. - It (Sentences begin with a capital letter.) - while (Most of the time, "when" refers to a moment or a completed action and "while" refers to time period or an action in progress. Examples: He was walking, when it started to rain. While he was walking, it started to rain.) - he wasn't wearing a jacket (negation of an incomplete action) - he didn't have an umbrella (have is a stative verb - "he wasn't having" is not permitted) - (alternative) he wasn't carrying an umbrella (negation of an incomplete action) 2. The game had already started when we turned on the TV. Japan lost (was losing) 1:0 and they were playing badly. ==> 2. The game had already started when we turned on the TV. Japan was playing badly and was losing 1:0. (A description of the game immediately after turning on the TV.) or 2. The game had already started when we turned on the TV. Japan played badly and last 1:0. (A description of the result of the game.) 3. We had cut (been cutting) down on sweets for 2 months before we started working out, ==> Either is acceptable. In this case, the meaning doesn't change. "We had cut down on sweets" emphasizes the results or that it the activity was not ongoing. "We had been cutting down on sweets" emphasizes the activity and that it was ongoing.

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