It was after shortly microscopes were introduced at the beginning of the seventeenth century that micro organisms were actually sighted.

Last night there was .......... singing outside my house. 

Among the parameters that determine whether an environment is suitably for life as we know are temperature, water availability, and oxygen content.

Yogurt contains a higher percentage of lactic acid than another fermented milks, and it is rich in B-complex vitamins.

A number of the Pacific Islands are volcanoes that have pushed up from the ocean floor, the others are the tops sunken mountain ranges

Most bats roost in crevices, caves, or building by day and are active at night or twilight.

 “I’m too tired to study.” “If you hadn’t watched that late movie last night, you _____ so tired now.” 

It is becoming extremely difficult to grow enough to feed the world’s rapidly increased population.

Due to the latest forecast, the tunnel will be finished next year

Short-wave radios that can receive and transmit signals are used by pilots, the police, and amateur operator .

John has bought a dictionary, _    ?

The homes created by the legendary architect Frank Lloyd Wright are still viewed as uniquely innovative, and valuable.

According to classical musical tradition, the term “sonata” is given to those works are written for solo piano or for solo wind or stringed instrument.

The bold way in which Margaret Mead defined the terms “family” – based as much on choice as on biological relationship – is possibly the most enduring of her legacies.

Deciduous trees are ones that lose its leaves in the autumn and grow new ones in the spring.

Pop Art was a movement of the 1950’s and 1960’s whom imagery was based on readily recognized American products and people.

Keep trying to learn English. Don’t give up. Eventually, you will succeed, even though you may not know how much time it will cost

..................United States is ...................world's biggest consumer of energy. 

Time is of few count in relation to great thoughts that are as vivid today as when they first passed through the author’s minds ages ago

There are a lot of people attending the wedding party, _    ?

Many exercises such as calisthenics, running, or to swim involve producing muscle tension through a range of movements that are called isotonics.