在两个国家同时进行类似的实验。

___Parallel experiments are being conducted in both countries.

这本日记是一个通向他所称的平行世界的维度门户。

The diary was a dimensional portal to a ___parallel world he called Wonderland.

多年来，他们的职业生涯一直并行发展。

Their careers have followed ___parallel paths over the years.