过度肥胖是严重的问题。
The problem with this sort of thinking is that it seems to suggest history is not weighty, and there is not some degree of inertia in users.这种思考方式的问题是，似乎暗示历史并不久远，而且用户不存在某种习惯。
The problem is, there are too many aerosols in the atmosphere competing for water molecules, so the cloud droplets that form are too small and never become weighty enough to fall to the ground.问题在于，大气中争夺水分子的浮质是太多了，因此形成的云层的水滴变得极小，其重量始终达不到下降到地面的程度。
