Although, however, because, so and time connectors

Use because + clause to give a reason: We stayed home because it was raining.

Use so + clause to give a result: It was raining, so we stayed home.

Use although + clause to put two contrasting ideas inside one sentence: Although it was cold, we went out.

However usually links separate sentences or independent clauses and is commonly followed by a comma: It was cold. However, we went out.

Use time connectors such as when, while, before, after and as soon as to show when events happen; for future meaning, use a present form after when/as soon as rather than will.