a shift

A "shift" is the period of time that an employee has to work. Jobs that have "shifts" are usually paid by the hour. One shift is usually between 4 to 16 hours, and can sometimes have a name like:

• the late shift
• the morning shift
• the graveyard shift (a creative name for a shift that starts late at night and goes until early morning)

The verb "work" is sometimes used to talk about a shift. In a job with a shift system, you might hear an employee say:

"I'm working the afternoon shift tomorrow."

You need to (do something)

"You need to ___" is a really strong and direct way of giving someone advice or orders. It's usually used by parents, teachers, and bosses. It's usually used when they're angry or annoyed:

You need to stop talking and pay attention.

You need to get the account manager on the phone and tell him you're sorry, but you made a mistake.

arrive to (somewhere)

"Arrive to ___" is technically a mistake, but it's a mistake that English speakers often make. The correct form is "arrive at ___":

You need to arrive at the office at least fifteen minutes before the start of your shift.

To "arrive" means to get to a place. "Arrive" is a little bit more formal than "get to". So when telling somene a story, you might say:

I got to the party at around nine.

But if you were in a courtroom, telling a judge or lawyer about something that happened, you might say this:

I arrived at the party at nine o'clock p.m.

at least (a number) before (something)

You use the phrase "at least" to talk about the smallest or lowest number of something:

There were at least 20 people waiting in line already when I got there.

You can also use "at least" to talk about time:

I try to get to the airport at least 2 hours before the flight leaves.

This means that the speaker tries to arrive at the airport 2.5 or 3 hours before the flight leaves, but certainly no later than 2 hours before the flight.