acid and base in daily life

1.What does “it” refer to? (line 1)

• digestive juice

• stomach

• pH value

• acidic properties

2. The word “properties” means? (line 1)

• perfection

• invulnerability

• qualification

• powerfulness

3.

• dilute

• diluting

• diluted

• dilutes

4.

• absorbing 

• absorbed

• absorb

• absorbs

5.

• remains

• remains

• remaining

• remained

6.

• medicines

• medicine

• medicined

• medicining