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How to translate these sentences in Chinese?

I booked a one-way plane ticket to china for a really cheap price of only $ 500.
我花了500美元买了一张非常便宜的去中国的单程机票。

The flight will go start from San Francisco to Tokyo then to Beijing.
飞机从旧金山起飞沿经东京最后到北京。

I decided to split the cost of the plane ticket with my parents, I will pay to go China and they will pay for me to come back to America
我决定和我的父母平摊机票的费用，我买去中国的机票，他们买回美国的。

I booked a one-way plane ticket to china for a really cheap price of only $ 500.
我只花了500美元就订了一张去中国的单程飞机票
The flight will go start from San Francisco to Tokyo then to Beijing.
这次航班将从圣弗朗西斯科起飞，到东京中转，最后飞往北京
I decided to split the cost of the plane ticket with my parents, I will pay to go China and they will pay for me to come back to America
我决定和我的父母平摊此次飞机票的钱，我会自费飞往中国，他们帮我买回美国的票