Breakdown of Die Spionin versucht, den Fremden zu beobachten.
versuchen
to try
zu
to (infinitive marker)
beobachten
to observe, to watch
die Spionin
the spy (f)
Questions & Answers about Die Spionin versucht, den Fremden zu beobachten.
Why is the word for "the stranger" spelled den Fremden with an -n at the end?
Fremden is a nominalized adjective, meaning it's an adjective (fremd) acting as a noun. Even though it's capitalized like a noun, it still takes adjective endings! Here, it is the masculine direct object (accusative case) following the definite article den. Just like you would say den fremden Mann, the nominalized version becomes den Fremden.
How would this sentence change if the spy were observing a female stranger?
It would change to: Die Spionin versucht, die Fremde zu beobachten. For a woman, you use the feminine accusative article die. Following a definite article in the feminine accusative, the adjective ending is -e, so fremd becomes Fremde.
Die Spionin is also a person. Why doesn't it get adjective endings like Fremden does?
Because Spionin (spy) is a standard noun, not an adjective turned into a noun. It is built from the masculine noun der Spion by adding the feminine suffix -in. The special adjective ending rules only apply to words that originally started as adjectives (like fremd, bekannt, or deutsch).
Why is there a comma after versucht?