布诺斯艾利斯在下雨(i think it's kind of like a status)。街上的人比平时少。虽然天气预报预言了下雨(though it sounds a little weird but there's nothing wrong with the grammar)，但是许多人没有准备就离开了(usually 了means things already happened)家，没带雨伞(umbrella)或者雨衣。现在人行道的在屋顶下有些人在等雨停了或者小一些。有些人冒雨(means through the rain)行走(i have no idea how to express exactly what you are trying to say in chinese though i understand it. we don't really have that kind of expression)。

至于我，我有一把雨伞，但是我的脚还是无可避免(prevent)地湿了。布诺斯艾利斯的人行道很槽糕(we usually just say it's bad instead of it's not good)，我得小心别踩松动的砖，别让水溅到我的裤子。我也得小心别我的雨伞和别的人的雨伞磕碰。这其实是一个很难的任务。

不管怎样，这么坏的天气让你什么都不想做，只想留在家里安静地睡觉或者伴着雨声(with the sound of raindrops)看书，而不是去办公室在剩下的时间里努力地工作。

This is more or less what I tried to wirte in Chinese (thanks in advance for your corrections):

It is raining in Buenos Aires. There are less people than usual on the streets. Even though the forecast had predicted it, many people have not left their homes prepared for it and have not taken an umbrella or raincoat with them. Now some of them are waiting under roofs on the sidewalks for the rain to stop or at least drop a little. Others just walk through the rain making the faces people usually make when getting wet under the rain.

As for me, I have got an umbrella. However, it does not prevent my feet from getting a bit wet. Sidewalks in Buenos Aires are not in the best condition so I have to be careful not to step on loose tiles and splash water on all over my trousers while I also try to avoid clashing my umbrella with those of the other pedestrians. It is certainly a difficult and annoying task.

Anyway, the weather is awful enough to bring down your spirit and make you just want to be at home peacefully sleeping or reading a book while hearing the rain fall down, instead of going to the office and spend the rest of the day working hard.