請問呢後英文有咩錯左?? 20點

A merchant mariner spend extended periods at sea, and earns leave. Most are
hired for one or more voyages that last of several months, although there is no
job security after that voyage. Merchant marine officers and seamen, both
veterans and beginners, are hired for voyages through union hiring halls or
directly by shipping companies. Hiring halls prioritize the candidates by the
length of time the person have been out of work, and fill open slots accordingly. Hiring halls are typically found in major seaports.
At sea, these workers usually stand watch for 4 hours and are off for 8 hours,
7 days a week. Those employed on Great Lakes ships work 60 days and have
30 days off,
but do not work in the winter when the lakes are frozen. Workers on rivers,
canals, and in harbors are more likely to have year-round work. Some work 8- or
12-hour shifts and go home every day. Others work steadily for a week or month
and then have an extended period off. When work, they are usually on duty for
6 or 12 hours and are off for 6 or 12 hours.
People in water transportation occupations work in all weather conditions.
Although a merchant mariner tries to avoid severe storms while at sea, working
in damp and cold conditions is often inevitable.
While it is uncommon nowadays for vessels to suffer sea disasters such as fire, explosion, or a sinking, workers face the possible that
they may have to abandon their craft on short notice if it collides with other
vessels or guns around.
They also risk injury or death from falling overboard, and hazards associated with
working with machinery, heavy loads, and dangerous cargo.

作業自己做啦，夠鐘架喇，相信冇人可以幫到你。