•Take heed (of sth) (idiom) -

To pay close attention to something and be careful about it.（关注，留意）

Examples:　　

1.He didn't take heed of the doctor's advice, and now he's struggling to survive. 

2.The government was taking little heed of these threats.

•Opt for (sth) (phrasal verb) -

To choose some option in preference to others.（（优先）选择）

Examples:　　

1.After recent setbacks in the market, most people are now opting for low-risk investments. 

2.The kids opted for a trip to Disneyland instead of Ocean Park.

•Synergy (noun) -

The interaction or cooperation of two or more organizations, substances, or other agents to produce a combined effect greater than the sum of their separate effects.（协同作用，增效作用）

Examples:　　

1.Team work at its best results in a synergy that can be very productive. 

2.Profitability is expected to benefit from synergies between the two operations.

•Down-to-earth (adjective) -

Practical and direct in a sensible, honest way.（务实的，脚踏实地的）

Examples:　　

1.Their ideas seem to be far more down-to-earth and sensible. 

2.She's a down-to-earth woman with no pretensions.

•Opportunity knocks but once (proverb) -

You will only have one chance to do something important or profitable.（机不可失，时不再来）

Examples:　　

1.Opportunity knocks but once - if you don't accept the job in France now, you'll never go!  

2."Opportunity knocks but once," her father said, "and this may be your only chance to get a good education."