........................

`33.` Some scientists believe that mobile phones are responsible for some health problems.

`->` S + believe that + S + V

`->` Be + responsible for + Ving/st : Chịu trách nhiệm về

`34.` There was an increased demand for travel, so the government decided to invest in building the metro system.

`->` There + was/wasn't + a/an + adj + N

`->` Decide + to V | Invest in + Ving

`33. ` Some scientists believe that mobile phones are responsible for some health problems.

gt:

to believe that S-V: tin rằng

to be responsible for st: chịu trách nhiệm về

`35. ` There was an increased demand for travel, so the government decided to invest in building the metro system.

gt:

to be an increased demand for st: là nhu cầu ngày càng tăng đối với

decide to do st: quyết định làm gì

invest in st/Ving: đầu tư cái gì

so - clause: vì vậy