Tenses in English Grammar

The Sun ________ light and heat to sustain life on Earth.

• provides

• provided

• providing

• provide

Scientists ________ a new experiment to test the hypothesis at the moment.

• conduct

• are conducting

• conducted

• conductive

Researchers ________ significant progress in cancer treatment over the last decade.

• make

• making

• have made

• made

The data collectors ________ data for the past six hours.

• collect

• collecting

• have been collecting

• collected

Darwin ________ his theory of evolution during his voyage on the HMS Beagle.

• developed

• develop

• developing

• had developed

While the researchers were analyzing the samples, the equipment ________ unexpectedly.

• malfunctioned

• malfunctions

• malfunction

• have malfunctioned

Before the discovery of antibiotics, infectious diseases ________ many lives.

• claim

• had claimed

• claims

• have claimed

By the time they arrived at the laboratory, the scientists ________ for over twelve hours.

• work

• working

• had been working

• worked

By the time they arrived at the laboratory, the scientists ________ for over twelve hours.

• work

• working

• had been working

• worked

The next space mission ________ new insights into Mars' geological features.

• will provide

• provides

• provide

• providing