Although not quite as effective as the paper funnel method, this method utilizes the same approach: lure the fruit flies into the trap with a small opening and make it hard for them to exit. The type of bait doesn't matter as much as the quantity; you probably want at least an inch of sweet liquid covering the bottom of the bowl. Here are some suggestions for sweet concoctions that work well as bait:  Put a piece of old, skinless fruit, such as an orange or a banana, along with some balsamic vinegar in a bowl. Experiment with a mix of white wine and coriander seeds. This mixture seems to work well. Add a bit of white wine vinegar to make the concoction even more pungent. A mix of honey, sugar, and balsamic vinegar also works in a pinch. Use a large sheet of plastic wrap to completely cover the bowl. Try to get the plastic wrap as taught as possible. Try to keep the holes as small as possible; large holes can let the flies escape back out again. The point is to lure the fruit flies into the bowl and make it extremely hard to get back out. If using a fork makes the holes in the plastic wrap too big, try switching to a sharp toothpick in order to prick small holes in the plastic wrap. Come the next day, you should see fruit flies caught inside the plastic wrap, happily feasting on the bait. If you haven't managed to trap any flies, check to make sure the holes in your plastic wrap aren't too big. It's probably best to take the trap outside before killing the fruit flies so that any escapees don't reinfest your kitchen. Take off the plastic wrap and kill the fruit flies inside by pouring a mixture of warm water and dish soap into the container. The soap works to reduce the surface tension of the water and cause the flies to drown. Wait a minute or two, then discard the contents of the jar. When you're finished flushing the fruit flies, rinse the jar with hot water and reuse it to make a new trap.

TL;DR in Chinese:
准备一个大碗或中碗。 在中碗或大碗底部放一些甜诱饵。 用保鲜膜紧紧盖着碗。 用叉子或其它工具在保鲜膜上戳多个小洞。 把陷阱摆放在果蝇为患的地方一整夜。 处置捉到的果蝇。