請大家幫我看看這段英文有沒有語病?謝謝~!

題目：

請大家幫我看看這段英文有沒有語病?謝謝~!
He kept testing the performance of the car and improving its mechanical structure, and finally he solved all the difficulties, with the car crossing over the obstacle and the gap smoothly.
或者大家有好的修改建議也行,謝謝~!
原中文是：他不斷測試小車的性能,改進小車的結構,終於解決了所有的困難,小車可以平穩的越過障礙和溝.
如果寫成with the car can cross over the obstacle and the gap smoothly,就有語病了吧？是麼？

解答：

沒有什麼大語病,有一個詞用的不恰當,試試把gap 改成 ditch,並用複數.ditch:a long,narrow excavation made in the ground by digging,as for draining or irrigating land; trench.
gap:a break or opening,as in a fence,wall,or military line; breach:We found a gap in the enemy's line of fortifications.
就是說ditch才是指地上的溝.
補充：
1.重新查了一次漢英字典,溝：ditch/gully,其中ditch比較常用一點.gap的中文是裂縫/缺口.所以我還是堅持用ditch.
2.同意用handle the difficulties.solve the problems是解決問題的意思,離原意有一點遠.
3.with the car can cross over...絕對有語病.
4.cross over 有一種過到馬路或河的另一面的意思,建議用drove over.
here is my try:他不斷測試小車的性能,改進小車的結構,終於解決了所有的困難,小車可以平穩的越過障礙和溝.
He kept on testing the performance of the car,improving its structures,and eventually handled all kinds of difficulties.The car drove over the obstacles and ditches smoothly.