Sherlock Holmes and Doctor Watson joke

Sherlock Holmes and Doctor Watson go camping. In the moing, as they are lying in their sleeping bags, Holmes says, 'Watson, look up at the sky and tell me what you deduce.' So Watson says, 'Well, the sky is salmon pink, so we're going to have a clear day. The moon is just setting, so it must be about 5 am. There are no clouds, so it probably won't rain.' Holmes bursts out, 'Watson, you idiot! Someone has stolen our tent.' 

به‌ «کاربرد‌ زمان‌ حال‌ در شرح‌ رویدادهاى گذشته»‌ (historical present) توجه کنید.