What is this passage mainly about?

How the Moon and Sun create a tidal rhythm that local geography reshapes (The passage combines astronomical causes with the local effects of continents, coasts, and seafloor.)

Which local features can change a coast’s tidal pattern?

The shapes of continents, coasts, and the seafloor (The third paragraph names continents, coast shape, and seafloor shape.)

A “diurnal” tidal pattern has

one high and one low tide during a tidal day (The passage defines diurnal as a pattern with one daily high, paired with one low.)

When are tidal ranges usually smaller than at new or full moon?

Near quarter moons, when the Sun and Moon pull in different directions (The final paragraph contrasts the combined alignment with the different directions near quarter moons.)

Why the Sea Rises and Falls: Level 2 Reading Comprehension Questions

At many coasts, the sea rises and falls twice during a tidal day. At some places it rises and falls once, and at others the two daily tides have different heights. These patterns are tides, caused mainly by the Moon’s gravity and also by the Sun.

The Moon’s pull is stronger on the side of Earth nearer the Moon than on the far side. In a simple picture, this difference produces two broad tidal bulges. As Earth turns, a coast moves through the pattern.

Real oceans do not cover a smooth, round Earth. Continents block the water, and the shapes of coasts and the seafloor change how it moves. That is why local tides may be semidiurnal, with two similar highs; diurnal, with one; or mixed, with two unequal highs.

The Sun changes tidal range too. Near new and full moons, the Sun, Moon, and Earth line up, so their effects combine to make larger spring tides. Near quarter moons, their directions differ and the range is usually smaller. A tide table uses local measurements and predictions because the Moon supplies the main rhythm, but each coast reshapes it.

Comprehension questions