Hitting the homestretch in fall: on a former railroad bridge in the Great Allegheny Passage in Pennsylvania.

在秋天里返家的最后旅途上冲刺：在之前宾夕法尼亚州阿勒格尼大公路的铁道桥上。

youdao

This functioned as a selective bridge, permitting the passage of positively charged sodium ions, but not negatively charged chloride ions.

它可以作为有选择的桥梁让带正电的钠离子通过，同时阻止了带负电的氯离子。

youdao

If that still need to praise and description of the fall, it would be difficult passage across the bridge project.

如果说秋天仍需要赞美和描写，那将是一段文字桥梁难以跨越的工程。

youdao