F2 1st Term IS WS 03 Answers

1st Term WS 03 Submission date：_____________ Name：______________________ Class & no.：2 _________(     )

7.1       What is air made up of?

C. Breathed air and unbreathed air

i      Words to know:

	English term	Write the words again	Chinese term
1	Breathed air	Breathed air	呼出的空氣
2	Unbreathed air	Unbreathed air	未經呼吸的空氣

i      Fill in the blanks:

The table below shows the comparison比較 between unbreathed air and breathed air:

	Unbreathed air	Breathed air
Nitrogen	About 78%	About 78% (Same)A
Oxygen	About 21% (More)	about 16% (Less)
Carbon dioxide	About 0.04% (Less)	About 4% (More)
Water vapour	Variable多變的	Saturated (More)
Temperature	Lower	higher

i      Writing skill:

           Fill in the blanks and write sentences about the comparison between unbreathed air and breathed air. You may use the words ‘more’, ‘less’, ‘higher’ and ‘lower’.

1        (a)     Compared with breathed air, unbreathed air has more oxygen.

(b)     Compared with breathed air, unbreathed air has less carbon dioxide.

(c)     Compared with breathed air , unbreathed has less water vapour.

(d)     Compared with breathed air, unbreathed has lower temperature.

2        (a)     Compared with unbreathed air, breathed air has less oxygen.

(b)     Compared with unbreathed air , breathed air has more carbon dioxide.

(c)     Compared with breathed air, unbreathed air has less water vapour.

/ Compared with unbreathed air, unbreathed air has more water vapour.

(d)     Compared with unbreathed air, breathed has high temperature.