-----------------------------------
ながら， 乍ら
1. while, during, as
2. while, although, though, despite, in spite of, notwithstanding
3. all, both
4. as (e.g. "as always", "as long ago"), in (e.g. "in tears")
5. while doing something else (at the same time)
同时，……期间，一边……一边