What does this sentence 1

(1) 1Natural persons who have a domicile or their habitual abode in Germany are subject to unlimited income tax. 2The portion due to the Federal Republic of Germany also belongs to Germany within the meaning of this law
1.
in the exclusive economic zone, as far as there
a)
the living and non-living natural resources of the waters above the seabed, the seabed and its subsurface are explored, exploited, conserved or managed,
b)
other activities for economic exploration or exploitation of the exclusive economic zone are carried out, such as the generation of energy from water, currents and wind or
c)
artificial islands are erected or used and facilities and structures are erected or used for the purposes specified in letters a and b, and
2.
on the continental shelf, as far as there
a)
whose natural resources are explored or exploited; Natural resources in this sense are the mineral and other non-living resources of the seabed and its subsoil as well as the living beings belonging to the sedentary species that either remain immobile on or under the seabed or are only in constant physical contact with the seabed or be able to move around its subsurface; or
b)
artificial islands are erected or used and facilities and structures are erected or used for the purposes specified in letter a.
(2) 1German citizens who
1.
have neither a domicile nor their habitual abode in Germany and
2.
are employed by a domestic legal entity under public law and receive wages from a domestic public fund,
as well as relatives belonging to your household who are German citizens or receive no income or only income that is exclusively subject to domestic income tax. 2This only applies to natural persons who, in the state in which they have their domicile or habitual abode, are only entitled to a tax on income to an extent similar to the limited income tax liability.
(3) 1Upon request, natural persons who have neither a domicile nor their habitual abode in Germany will also be treated as subject to unlimited income tax, provided they have domestic income within the meaning of Section 49. 2This only applies if their income is subject to at least 90 percent of German income tax in the calendar year or if the income that is not subject to German income tax does not exceed the basic tax allowance according to Section 32a (1) sentence 2 number 1; this amount is to be reduced insofar as it is necessary and appropriate according to the circumstances in the taxpayer's country of residence. 3Domestic income, which, according to an agreement to avoid double taxation, may only be taxed to a limited extent in terms of amount, is deemed not to be subject to German income tax. 4In determining the income according to sentence 2, income that is not subject to German income tax and is not taxed abroad is not taken into account if comparable income is tax-free in Germany. 5Another prerequisite is that the amount of income that is not subject to German income tax is proven by a certificate from the competent foreign tax authority. 6The tax deduction according to § 50a is to be made regardless of sentences 1 to 4.
(4) Natural persons who have neither their domicile nor their habitual abode in Germany are subject to limited income tax liability, subject to paragraphs 2 and 3 and Section 1a, if they have domestic income within the meaning of Section 49.