back and forth

back and forth: in a backward and forward motion

• The restless lion kept pacing back and forth a long the front of its cage.
• Grandmother finds it relaxing to sit in her rocking chair and move back and forth.

going in one direction and then in the opposite direction, and repeating this several times:

• We travel back and forth all the time between Canada and England.
• He was pacing back and forth.

to get used to

to get used to: to become used to, to become adjusted to

This idiom describes the process of change that allows someone to be used to a situation, action, or habit.

• It took Yoshiko a long time to get used to the food that her American host family served her.
• Mark can't seem to get used to wearing contact lenses; recently he's been wearing his glasses a lot.

Hesitation

Hesitation (n)

when someone hesitates

• After some hesitation one of them began to speak.

without hesitation

• He agreed without hesitation.

have no hesitation in doing something

• I would have no hesitation in recommending Philip for the position.

a slight/brief/momentary etc hesitation

• There was a slight hesitation in Jamie's voice.

curious

curious (adj) : wanting to know about something

• Puppies are naturally curious.
• Her curiosity aroused, Mrs. Huber tried to think of a reason for dropping in on me unannounced.

curious about

• He was curious about how she would react.

astonishing

Astonishing (adj): so surprising that it is difficult to believe [= amazing]

• an astonishing decision
• their astonishing success
• That's why it was so astonishing when I decided to go to my hallway closet to retrieve a revolver that had never been used. 

astonishingly (adverb)

• an astonishingly good voice

newsworthy

Newsworthy (adj): important or interesting enough to be reported in newspapers, on the radio, or on television:

• newsworthy events
• Normally, there's never anything newsworthy about my life.

come across

Come across (v)

come across somebody/something: to meet, find, or discover someone or something by chance

• I came across an old diary in her desk.
• I've never come across anyone quite like her before.
• When you read this morning's paper, you may come across an article about the unusual day I had last week.

predicament

predicament: a difficult or unpleasant situation in which you do not know what to do, or in which you have to make a difficult choice

• the country's economic predicament
• She went to the office to explain her predicament.

in a predicament

• Other married couples are in a similar predicament.

Fill somebody in/Clue somebody in

Fill somebody in (v)

tell someone about recent events, especially because they have been away from a place

• I think you'd better fill me in on what's been happening.
• Having been absent from last meeting, I'd like to have you fill me in on what happened.

Clue somebody in (v)

to give someone information about something

clue somebody in on/about

• Somebody must have clued him in on our sales strategy.

to Chat somebody up

to Chat somebody up

British English/informal/to talk to someone in a way that shows you are sexually attracted to them:

• I spent the evening chatting up Liz.

Chat-up line (n)

British English/ something that someone says in order to start a conversation with someone they think is sexually attractive