1. The topic about the solar system was ___ interesting for me.
a. unhappy
b. useless
c. really

2. The water is colorless, odorless, and _.
a. careless
b. restless
c. tasteless
d. useful
e. priceless

3. Smoking is an _ habit that many people practice around the world.
a. unhealthy
b. unclean
c. unconditional
d. unheard

4. When you work as a secretary, you cannot be _.
a. impolite
b. improper
c. impatient
d. impossible

5. Pollution causes many disasters to the environment; for example, the water becomes ___ day by day.
a. unavailable
b. uncertain
c. unbreakable
d. undrinkable

Tasteless is the correct completion for the sentence 'The water is colorless, odorless and.................'. Water is considered tasteless because it lacks a distinctive flavor.

Undrinkable is the word that best fits the sentence 'Pollution causes many disasters to the environment, for example the water becomes.....undrinkable day by day.' Polluted water is unsafe for consumption.

Unhealthy would be the appropriate choice for 'Smoking is an...... habit that many people practice around the world.' Smoking is widely recognized as a harmful, unhealthy habit.

Learn more about Water properties and pollution effects here:

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